This appears to be a wide issue effecting a large number of people, or at least that's how it appears having seen lots of similar posts in the Community. I too have been having similar issues.
After contacting Fitbit support team they came back to me with the following resolution:
- Check if your Android's version on your phone has an update pending to be downloaded, if so, downloaded and move on to the rest of the steps, do the same if there is not an Android software update pending.
- Uninstall the Fitbit app from your phone.
- Restart your phone,
- Install the Fitbit app back.
- Log back into the app.
- Sync.
- Monitor this for a while.
I did all of the above but still have the issue. I have gone back to Fitbit support team to advise the above steps didn't fix the issue and that this is obviously a wide issue as so many people in the Fitbit Community are also having similar problems. They have now responded with the following:
Thanks for letting us know about this issue. We’re aware of it and are working to identify a resolution as quickly as possible.
We're sorry for any trouble. We appreciate your patience and look forward to getting you back on track.
I'll let you know if I hear back from them again with a resolution that fixes the problem.
